Various food and beverage systems are known in the art for blending a concentrate of relatively high viscosity with a diluent having a relatively low viscosity. Typical post mix food and beverage dispensers are designed to separately store and to automatically combine at the time of dispensing a concentrate and a diluent such as water at a predetermined ratio in order to consistently produce a food or beverage which is acceptable for consumption.
Certain pure beverage concentrates, such as milk, creamer and brewed ice tea, become unstable when contaminated by contact with the diluent, airborne bacteria, bacteria present on human hands, or from reusable parts which have not been properly sanitized. This need for a bacteria-free, controlled environment when using pure food and beverage concentrates in current art results in costly dispensing systems, high distribution handling and storage expenditures and expensive cleaning and sanitizing systems/procedures to be utilized by the operator wishing to offer these pure products to consumers.
One general attempt in current art to prevent contamination of the concentrate is to add preservatives to the concentrate which retard bacteria growth. Post mix food and beverages containing preservatives are less desirable to the consumer because of the foreign taste created by the addition of the preservative or due to the fear on the consumer's part that consuming the preservative may cause a health risk at some future point.
Another attempt in current art to retard bacteria growth is to house the pure food and beverage base concentrates in a refrigerated, automatically controlled and managed environment throughout the life of the concentrate beginning with the production stage and ending with the consumption stage. This refrigerated method to retard bacteria growth is a very costly method requiring expensive refrigerated handling, warehousing and monitoring, and uninterrupted electrical supply and regular maintenance of the refrigeration equipment throughout the distribution chain in addition to requiring a post mix dispenser having a refrigerated holding environment. Still, the possibility of bacteria growth exists if the reusable food zone parts of the refrigerated post mix dispenser are not thoroughly cleaned and sanitized at regular intervals.
Another attempt in current art to retard bacteria growth is to incorporate in the post mix dispenser, an automatic hot water sanitizing cycle at regular intervals of the reusable food zone parts. This method is also a costly one requiring regular monitoring and maintenance of the hot water sanitizing components to ensure the proper temperature is maintained, the proper volume of hot water is dispensed at the proper intervals and that emergency electrical power is available in the event a publicly supplied power outage occurs.
Another attempt in current art to retard bacteria growth is to prevent the pure concentrate from coming into contact with the diluent until it reaches the vessel from which the reconstituted food or beverage is delivered for consumption. This method is commonly referred to as the “split flow” method whereby concentrate is metered through its self-contained tubing which is an integral component of its packaging, ejected from this tubing separate from but in conjunction with a diluent stream directly into the consumption vessel. In many cases, this method is not desirable by the consumer because of the inadequate mixing results either visible or in the tasting of the reconstituted mixture, or because of the unsightly dual streams of concentrate and diluent entering the serving vessel during the dispensing cycle. Still, the possibility of bacteria contamination of the exposed outlet end of the concentrate tubing exists should it be opened with a contaminated instrument such as a scissors or knife or should it come into contact with airborne bacteria. Of course, there is always the possibility that the mixed beverage could be delivered into a contaminated container or come into contact with contaminated human hands, but these situations are beyond the design of the post mix dispenser and the dispensing assembly.
It is therefore desirable that a food and beverage dispensing system be able to utilize pure, preservative-free concentrates without depending or relying on a refrigerated environment inside the dispenser, refrigerated handling and storage of the concentrate, a manual nor an automatic hot water sanitizing cycle to prevent or retard bacteria growth, the cleaning and sanitizing of reusable food zone parts, the separation of concentrate in water when exiting the dispenser and a continual source of electricity to stop or curtail bacteria growth. It is further desirable that the food and beverage concentrate container along with its tubing, a vented cap/plug valve and its dispense spout be disposable once acceptable evacuation of the concentrate is achieved. It is further desirable that the vented plug valve and dispense spout also function as a non-mechanical pump, combining the food or beverage concentrate with the diluent to produce a mixture of uniform consistency when post mix dispensing occurs.
One example of a disposable dispensing assembly and mixing valve which aims to improve sanitation of the beverage dispenser is disclosed in U.S. Pat. No. 4,750,645 issued Jun. 14, 1988 to Wilson et al. In this design, however, concentrate is apt to remain in the mixing valve even after the mixed product is dispensed thereby creating a host for bacterial growth and contamination. In addition, this mixing valve includes a turbulence-producing, flow restriction which prevents its use as a non-mechanical pump. Further, this valve can be improved to enhance the mixing, sealing and delivery of the combined concentrate and diluent.